双去甲氧基姜黄素对朱砂叶螨的生物活性及作用方式

在室温26℃±1℃、湿度60%～80%、光照14 h条件下,测定了天然植物活性成分双去甲氧基姜黄素对重要植食性害螨朱砂叶螨各螨态的触杀和熏蒸活性,对幼螨、若螨、成螨的驱避活性,以及对雌成螨的产卵抑制活性.采用玻片浸渍法测得双去甲氧基姜黄素对朱砂叶螨雌成螨48 h的LCso为0.433 mg·mL-1.在0.883 mg·mL-1(LC70)的浓度下,双去甲氧基姜黄素对朱砂叶螨不同螨态触杀活性的大小依次为幼螨＞若螨＞成螨＞卵,其中对幼螨24h和48 h的校正死亡率分别为60.0%和83.3%;对朱砂叶螨各螨态的熏蒸作用不明显,024h和48 h的校正死亡率均小于3%;对幼螨、若螨以及成螨均表现出较强的驱避作用,其中对幼螨的效果最好,不同处理时间的驱避率均在85%以上,其次是若螨,对成螨的驱避性相对较差,72 h的驱避率仅为47.8%.同时对雌成螨有明显的产卵抑制作用,处理后120 h产卵抑制率达到89.3%.表明双去甲氧基姜黄素对朱砂叶螨的主要作用方式为触杀、驱避和产卵抑制作用.     

紫背金盘(Ajuga nipponensis)次生物质对桔全爪螨(Panonychus citri)的驱避作用

研究了紫背金盘Ajuga nipponensis Makino各溶剂提取物和部分化合物对桔全爪螨Panonychus citri McGregor雌成螨及其产卵的驱避作用.结果表明,石油醚萃取物、乙酸乙酯萃取物具有较强的生物活性.在0.1 g · L-1时, 石油醚和乙酸乙酯萃取物对该螨处理1d后的产卵忌避率分别为:84.86%、69.88%;2d后为89.49%、82.19%;对雌成螨驱避率分别为:85.08%、68.66%;2d后为50.96%、69.84%.乙酸乙酯萃取物经分离得到四类化合物,结果表明:馏分Ⅰ为长链脂肪酸混合物,具有较强生物活性,2000μg/ml和1000μg/ml处理1d后,产卵忌避率分别为:80.77%、74.77%;2d后为73.81%、72.59%.2000μg/ml处理1d后对雌成螨的驱避率为:69.88%;2d后为74.24%.刺槐素Ⅱ、新克罗烷化合物Ⅲ和β-蜕皮甾酮Ⅳ在2000μg/ml均不表现活性.对馏分Ⅰ中的4个主要化合物单体进行活性测定,结果表明:十六烷酸、十六烷酸甲酯、十六烷酸乙酯和十八烷酸甲酯在2000μg/ml处理时,1d后,产卵驱避率分别为:75.18%、61.76%、59.18%和66.49%;2d后产卵驱避率为:66.67%、31.15%、46.75%和44.84%;雌成螨驱避率分别为:1d后,67.53%、63.79%、59.26%和68.00;2d后,67.23%、43.96%、48.23%和64.19%.在1000μg/ml处理时,1d 后,产卵驱避率分别为:59.21%、59.16%、57.02%和61.40%;1d后,雌成螨驱避率分别为:69.64%、61.43%、55.76%和64.00%.     

姜黄素类化合物对朱砂叶螨的生物活性

分别用玻片浸渍法和叶片浸渍法测定了从姜黄中分离的姜黄素(curcumin,CCM)、去甲氧基姜黄素(demethoxycurcumin,DMC)和双去甲氧基姜黄素(bisdemethoxycurcumin,BDMC) 3种天然姜黄素类化合物对朱砂叶螨Tetranychus cinnabarinus Boisduval的成螨、若螨、卵的触杀活性以及对成螨产卵的抑制作用。结果表明：3种化合物对朱砂叶螨的生物活性大小依次为BDMC>DMC>CCM。3种化合物对朱砂叶螨成螨触杀活性最高者为BDMC,处理24 h和48 h其LC₅₀分别为1.18和0.51 mg/mL。对若螨触杀活性的大体趋势与对成螨的相同,其中处理48 h,BDMC对若螨的LC₅₀最小,为2.48 mg/mL。3种化合物对朱砂叶螨卵的触杀毒力也同样表现为BDMC>DMC>CCM。3种单体化合物都表现出一定的对朱砂叶螨雌成螨的产卵抑制作用。对姜黄素类化合物构效关系的初步研究,明确了甲氧基在姜黄素模板上对杀螨活性的贡献,对于开发具经济价值的叶螨类杀螨剂或者筛选先导化合物模板,具有一定的参考价值。     

迷迭香油和花椒油对朱砂叶螨的生物活性

【目的】明确室内条件下迷迭香油和花椒油对朱砂叶螨Tetranychus cinnabarinus (Boisduval)的生物活性。【方法】采用熏蒸法和驱避法测定迷迭香油和花椒油对5日龄朱砂叶螨雌成螨的熏蒸活性、产卵抑制活性和驱避活性;并采用EthoVision XT6分析亚致死浓度下两种精油对雌成螨行为的影响。【结果】分别将5日龄雌成螨熏蒸处理12, 24和48 h后,迷迭香油对朱砂叶螨的致死率均显著高于花椒油处理组（P＜0.05）,且随着熏蒸时间的延长或精油浓度的升高,其熏蒸活性均增强;不同浓度的迷迭香油处理朱砂叶螨雌成螨24 h后的产卵抑制率均显著高于花椒油处理组（P＜0.05）。迷迭香油和花椒油处理朱砂叶螨雌成螨24 h的LC₃₀分别为6.731和120.142 μL/L;迷迭香油对朱砂叶螨雌成螨的驱避活性明显高于花椒油处理组。两种精油亚致死浓度处理朱砂叶螨雌成螨后,其自发运动方式发生了明显变化,移动频率在LC₁₀ 时呈现最高;且迷迭香油对朱砂叶螨雌成螨自发运动能力的影响比花椒油处理的影响更为明显。【结论】迷迭香油对朱砂叶螨的生物活性明显高于花椒油,因此,迷迭香油对朱砂叶螨的生物防治具有较高的应用价值。本研究为绿色蔬菜植物源杀螨剂的研究提供了科学依据。     

东莨菪内酯对朱砂叶螨的驱避和产卵抑制活性

本研究采用叶碟浸渍法测定了东莨菪内酯对朱砂叶螨Tetranychus cinnabarinus(Biosduvals)雌成螨的触杀活性,采用选择性的半叶法测定了驱避活性,同时采用非选择性的全叶法测定了产卵抑制活性。结果表明,东莨菪内酯对朱砂叶螨雌成螨具有较好的触杀活性,采用叶碟浸渍法处理48h后的LC50为0.297mg·mL-1,LC30为0.105mg·mL-1,LC10为0.023mg·mL-1。采用LC50、LC30和LC103个浓度的东莨菪内酯处理雌成螨后,发现东莨菪内酯对雌成螨没有表现出明显的驱避活性,处理区和对照区24h和48h的着螨率均为50%左右;采用LC50和LC102个浓度处理雌成螨后表现出了一定的产卵抑制活性,平均产卵抑制率分别为23.02%和13.23%,而LC30对雌成螨的产卵量表现出了促进作用,平均产卵抑制率为-8.25%,这可能是由于毒物兴奋效应所致。本研究旨在为东莨菪内酯的进一步开发和应用奠定理论基础。     

瑞香狼毒根提取物对山楂叶螨的生物活性

采用不同的生物活性测定方法比较了瑞香狼毒(Stellera chamaejasme L.)根部4种不同溶剂提取物的杀螨活性。结果表明,瑞香狼毒根提取物对山楂叶螨(Tetranychus viennensis Zacher)有很好的触杀和内吸活性。在触杀活性测试中,石油醚提取物和氯仿提取物的杀螨活性最高;在内吸作用中,乙醇、氯仿和石油醚提取物的杀螨活性均较高,杀螨效果显著。在对石油醚提取物的不同溶剂萃取物进行生物活性追踪测定中发现,石油醚萃取物和氯仿萃取物具有较高的生物活性,浓度为0.6 g.L-1,山楂叶螨的24 h校正死亡率分别达到93.22%和79.66%。     

木鳖子提取物对朱砂叶螨的触杀活性

测定了木鳖子提取物对朱砂叶螨的触杀活性。用甲醇、氯仿、石油醚3种不同极性的溶剂提取,石油醚提取率最高为30.79%,且对朱砂叶螨成螨和卵的触杀活性均高于其他两种溶剂的提取物,24 h校正死亡率分别为77.52%和72.04%。用甲醇对石油醚提取物萃取,发现甲醇萃取物活性明显高于石油醚部分,对成螨和卵处理24 h后的校正死亡率分别为89.60%和74.65%,产卵抑制率为62.74%,驱避率为58.23%。柱层析对甲醇萃取物进行分离得到10种组分,组分5活性最高,浓度为2 mg/mL时,24 h校正死亡率为86.15%。用薄层层析和气相色谱质谱联用仪分别检测组分5纯度和主成分,初步确定活性成分为α-菠菜甾醇。     

Monitoring pesticide resistance of Tetranychus cinnabarinus in Kunming' s flower regions

采用玻片浸渍法测定了昆明地区花卉朱砂叶螨Tetranychus cinnabarinus (Boisduval)对阿维菌素、甲氨基阿维菌素苯甲酸盐、溴虫腈、丁醚脲、炔螨特和哒螨灵的抗性.结果表明,昆明北郊和呈贡地区玫瑰上的朱砂叶螨雌成螨对阿维菌素与甲氨基阿维菌素苯甲酸盐产生了极高的抗药性,阿维菌素对2个地区的朱砂叶螨的LC50分别为40.25 mg·L -1和19.67 mg·L-1,相对毒力指数分别为敏感品系的2 441.08倍和1 192.86倍;甲氨基阿维菌素苯甲酸盐对其LC50分别为118.18 mg·L-1和9.24 mg·L-1,相对毒力指数是敏感品系的2 805.73倍和219.35倍.昆明北郊的朱砂叶螨对溴虫腈的相对毒力指数是敏感品系的2 371.40倍,呈贡和晋宁分别为162.01倍和173.38倍.丁醚脲对北郊、呈贡和晋宁朱砂叶螨的LC50分别为244.58 mg·L-1、385.41 mg·L-1和54.93 mg·L-1,相对毒力指数在3.01倍～21.10倍之间.北郊、呈贡和晋宁的朱砂叶螨种群对炔螨特和哒螨灵的LC50分别为155.39 mg·L-1、424.49 mg·L-1和62.70 mg·L-1,其相对毒力指数是敏感品系的6.45倍、17.63倍和2.60倍.朱砂叶螨对药剂抗药性水平趋势从高到低为:阿维菌素、甲氨基阿维菌素苯甲酸盐＞溴虫腈、丁醚脲＞炔螨特、哒螨灵,抗性最高的地区为昆明北郊,晋宁相对较低.     

栽培型和野生型黄花蒿提取物对朱砂叶螨杀螨活性比较

研究了野生型和栽培型黄花蒿叶丙酮提取物对朱砂叶螨的生物活性.结果表明:栽培型和野生型48 h的LC50分别为0.295和0.567 mg·ml-1,以栽培型的杀螨毒力较高;对2种提取物进行柱层析分离,野生型最终分离出19个馏分,栽培型分离出17个馏分,其中野生型的第11馏分与栽培型的第13馏分的杀螨活性在2.5 mg·ml-1,处理48 h的校正死亡率均为100%,与其他组分存在显著性差异;将杀螨活性较好的馏分进行毒力测定得出,处理48 h,野生型馏分11的LC50为0.120 mg·ml-1;栽培型馏分10、12和13的LC50分别为0.144、0.163和0.117 mg·ml-1.表明栽培型黄花蒿叶丙酮提取物对朱砂叶螨的触杀活性优于野生型.     

百里香杀螨活性成分的分离及鉴定

为了探讨百里香的杀螨活性成分,以山楂叶螨(Tetranychus viennensis)为供试对象,采用生物活性示踪法从百里香(Thymus mongolicus)乙醇提取物中分离纯化出5种活性成分,其化学结构经MS、1H-NMR、13C-NMR分析鉴定为百里香酚、香芹酚、松油烯-4醇、豆甾醇和β-谷甾醇.采用玻片浸渍法测试了5种化合物对山楂叶螨的触杀活性,结果表明,百里香酚和香芹酚对山楂叶螨有较强的触杀活性,12 h和24 h的触杀LC50值分别为0.103、0.135 mg·mL-1和0.048、0.096 mg·mL-1;松油烯-4-醇也有一定的杀螨活性,12 h和24 h的触杀LC50值分别为0.320和0.231 mg·mL-1;而两种甾醇类化合物β-谷甾醇和豆甾醇对山楂叶螨没有明显的触杀作用.分析认为百里香酚可能是百里香的主要杀螨活性成分之一.     

Bioactivity of the metabolites from endophytic actinomycete Fq24 against Tetranychus cinnabarinus

An endophytic actinomycete strain Fq24 was isolated from healthy tomato plants. The acaricidal substances in the metabolites from Fq24 were collected and identified by the methods of extraction, column chromatography, and gas chromatography-mass spectrometry (GC-MS), and their bioactivities against Tetranychus cinnabarinus were measured with slide-dip and leaf-residue methods. Among the extracts, petroleum ether extract had high bioactivity in contact toxicity and oviposition deterrent against T. cinnabarinus. Its lethal concentration of 50% (LC50) was 52.57 mg x L(-1), and its oviposition deterrent concentration of 50% (ODC50) was 43.18 mg x L(-1). The identification with GC-MS showed that the main chemical component of fraction S11 was methyl hexadecanoate, whose molecular formula was C17H34O2, being one of the substances with acaricidal activity in the metabolites from Fq24. The 24 h corrected mortality rate of female mite at 5 mg x mL(-1) of methyl hexadecanoate was 78.3%, and the oviposition deterrent rate was 81.6%.     

Signal transduction and hormone-dependent internalization of the thyrotropin-releasing hormone receptor in cells lacking Gq and G11.

The thyrotropin-releasing hormone (TRH) receptor was expressed in embryonic fibroblasts from mice lacking the alpha subunits of Gq and G11 (Fq/11 cells) to determine whether G protein coupling is necessary for agonist-dependent receptor internalization. Neither TRH nor agonists acting on endogenous receptors increased intracellular calcium unless the cells were co-transfected with the alpha subunit of Gq. In contrast, temperature-dependent internalization of [3H]MeTRH in Fq/11 cells was the same whether Gqalpha was expressed or not. A rhodamine-labeled TRH analog and fluorescein-labeled transferrin co-localized in endocytic vesicles in Fq/11 cells, indicating that endocytosis took place via the normal clathrin pathway. Cotransfection with beta-arrestin or V53D beta-arrestin increased TRH-dependent receptor sequestration. Fq/11 cells were co-transfected with the TRH receptor and a green fluorescent protein (GFP)-beta-arrestin conjugate. GFP-beta-arrestin was uniformly distributed in the cytoplasm of untreated cells and quickly translocated to the periphery of the cells when TRH was added. A truncated TRH receptor that lacks potential phosphorylation sites in the cytoplasmic carboxyl terminus signaled but did not internalize or cause membrane localization of GFP-beta-arrestin. These results prove that calcium signaling by the TRH receptor requires coupling to a G protein in the Gq family, but TRH-dependent binding of beta-arrestin and sequestration do not.     

Validation and Assessment of Three Methods to Estimate 24-h Urinary Sodium Excretion from Spot Urine Samples in Chinese Adults

24-h urinary sodium excretion is the gold standard for evaluating dietary sodium intake, but it is often not feasible in large epidemiological studies due to high participant burden and cost. Three methods—Kawasaki, INTERSALT, and Tanaka—have been proposed to estimate 24-h urinary sodium excretion from a spot urine sample, but these methods have not been validated in the general Chinese population. This aim of this study was to assess the validity of three methods for estimating 24-h urinary sodium excretion using spot urine samples against measured 24-h urinary sodium excretion in a Chinese sample population. Data are from a substudy of the Prospective Urban Rural Epidemiology (PURE) study that enrolled 120 participants aged 35 to 70 years and collected their morning fasting urine and 24-h urine specimens. Bias calculations (estimated values minus measured values) and Bland-Altman plots were used to assess the validity of the three estimation methods. 116 participants were included in the final analysis. Mean bias for the Kawasaki method was -740 mg/day (95% CI: -1219, 262 mg/day), and was the lowest among the three methods. Mean bias for the Tanaka method was -2305 mg/day (95% CI: -2735, 1875 mg/day). Mean bias for the INTERSALT method was -2797 mg/day (95% CI: -3245, 2349 mg/day), and was the highest of the three methods. Bland-Altman plots indicated that all three methods underestimated 24-h urinary sodium excretion. The Kawasaki, INTERSALT and Tanaka methods for estimation of 24-h urinary sodium excretion using spot urines all underestimated true 24-h urinary sodium excretion in this sample of Chinese adults. Among the three methods, the Kawasaki method was least biased, but was still relatively inaccurate. A more accurate method is needed to estimate the 24-h urinary sodium excretion from spot urine for assessment of dietary sodium intake in China.     

槲寄生中的化学成分及其抗肿瘤活性(Ⅰ)

从槲寄生75%乙醇提取物中分离得到4个化合物,应用波谱学方法鉴定它们的结构为尼克酰胺(1),乙酰胺(2),齐墩果酸(3),β-香树脂醇乙酸酯(4).其中,化合物1和2为首次从槲寄生属植物中分离得到.采用MIT法对化合物1～4进行体外抗肿瘤活性研究,结果显示化合物1、2和4对HO-8910人卵巢浆液性腺癌、SMMC7721人肝癌、T24人膀胱癌、HepG2人肝癌和SHG人神经胶质瘤细胞系没有细胞毒活性,化合物3则对这五种肿瘤细胞系有显著的抑制作用.     

Antimicrobial Susceptibility of Standard Strains of Nontuberculous Mycobacteria by Microplate Alamar Blue Assay

In this study, 24 standard nontuberculous mycobacteria (NTM) species strains including 12 slowly growing mycobacteria strains and 12 rapidly growing mycobacteria strains were subjected to drug susceptibility testing using microplate Alamar Blue assay-based 7H9 broth. The most active antimicrobial agents against the 24 NTM strains were streptomycin, amikacin, the fluoroquinolones, and the tetracyclines. Mycobacterium chelonae, Mycobacterium abscessus, Mycobacterium bolletii, and Mycobacterium simiae are resistant to most antimicrobial agents. The susceptibility results of this study from 24 NTM standard strains can be referenced by clinicians before susceptibility testing for clinical isolates is performed or when conditions do not allow for susceptibility testing. The application of broth-based methods is recommended by the Clinical and Laboratory Standards Institute, and the documentation of the susceptibility patterns of standard strains of mycobacteria can improve the international standardization of susceptibility testing methods.     

塔里木盆地荒漠盐碱生境土壤放线菌的初步研究

采用常规方法研究了新疆塔里木盆地荒漠盐碱生境土壤放线菌区系、放线菌的耐盐、碱性及对植物病原真菌的拮抗性。结果表明:土壤放线菌区系较单一,仅分离到链霉菌属和拟诺卡氏菌属,其中以链霉菌属为主(98.57%),链霉菌可分10个类群,以白孢类群为优势类群。土壤含盐量愈高,链霉菌组成愈简单。放线菌的最适生长盐浓度多集中在6%~8%,最适生长pH集中在7~8。24株供试放线菌中,有4株中度嗜盐放线菌对供试靶标菌有拮抗性,占供试菌的16.67%。     

Steroids from the aerial parts of Leonurus japonicus

Two new steroids, (24S)-stigmast-4,28-diene-24-ol-3-one (1) and mono-β-sitosteryl azelate (2), along with ten known analogues (3–12), were isolated from the ethanolic extract of Leonurus japonicus Houtt. Their structures were elucidated by spectroscopic and chemical methods. The absolute configuration of 1 was confirmed by single crystal X-ray crystallographic analysis using anomalous scattering of Cu Kα radiation. Compounds 3, 4, and 9 showed significant inhibitory activities against ADP-induced platelet aggregation, while compound 1 had a weak cytotoxic activity against acute myeloid leukemia cell line MV4-11.     

Comparative study of in vitro methods to analyse the antifungal activity of propolis against yeasts isolated from patients with superficial mycoses

AIM: To test a total of 15 strains belonging to four species of yeasts by different in vitro methods against propolis and itraconazole (ITC). METHODS AND RESULTS: Three methods were compared for susceptibility testing of yeast isolates to propolis: disc diffusion method, agar dilution method and National Committee for Clinical Laboratory Standards (NCCLS, M27A) broth microdilution method. ITC was selected as the antifungal agent for comparison study. Using the broth microdilution method, the geometric mean for MIC (microg ml(-1)) with regard to all isolates was < or =0.06 for propolis and < or =0.35 for ITC. The broth microdilution and the agar dilution methods were in good agreement (75%) for propolis against yeasts isolated from patients with superficial mycoses. Using the diffusion method, all strains showed a broad zone of inhibition at the first available reading time (24 or 48 h). An increase of MIC values was accompanied by a decrease of growth inhibition zone diameter. A favourable correlation was found between MIC and inhibition zone around the disc for propolis sample and the correlation coefficient was: r = -0.626 (P < 0.01). CONCLUSIONS: This study suggests the potential value of the agar dilution and disc diffusion method as a convenient alternative method for testing of yeasts to propolis. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrated that propolis and ITC were very active against yeasts from patients with superficial mycoses. The other prominent finding in this study is that RPMI 1640 with L-glutamine was the available broth for the in vitro susceptibility testing of yeasts.     

抗生素2,4-二乙酰基间苯三酚作为荧光假单胞菌2P24菌株生防功能因子的实证分析

荧光假单胞杆菌2P24菌株分离自小麦全蚀病自然衰退土壤,它是酚类抗生素2,4-二乙酰基间苯三酚(2,4-DAPG)的高产菌,对多种土传病害具有较好的防治能力。利用同源重组构建2,4-DAPG合成基因的定位突变体,并对突变体进行基因互补,通过检测突变菌株和恢复突变菌株抗生素产量和生防效果确定2,4-DAPG在菌株2P24生防功能中的作用。实验中,定位突变体丧失产生抗生素和拮抗病原菌的能力,而恢复突变体的抗生素产量和拮抗能力均恢复至野生菌水平。在对番茄青枯病的防病试验中,2,4-DAPG突变体的防效低且下降快,而恢复突变体的生防能力与野生菌相当,且效果稳定。由此可确定2,4-DAPG是菌株2P24防治番茄青枯病的主要因子,在防效上起关键作用。